The water in my 400 gal Goldfish pond has not been as clear as it used to be. Over the past few days I seen the water quality start to go down hill I thinking. This is my first year with a little front yard pond or any pond for that matter. It gets roughly 7 hours of sunlight a day before the shade sets in, in the afternoon. When I installed the pond I put a river type stone/ rock in the bottom and on the shelves of the pond. I'm not sure if that was a mistake or not. It looks like they are starting to get a green tinge on them! I also have a few larger pieces of grey lava rock that I noticed starting to get some green algae spots on them. I went to Lowe's today and got a water lily and some replacement pads for my mechanical filter. I secured the lily to a basket.....because it wouldn't sink to the bottom and then replaced the pads in the filter. When I took the filter box out of the water and opened the box,the water was discusting looking. nasty green color. The pads were even worse. Both pads were caked up with algae, so I replaced them both. was hat a mistake as well? I didn't touch the bio balls or empty the water that was in the filter. I put the filter box and the new replacement filter's back in the water and turned the pump/ fountain back on to cycle the water. I'm in the pond already at this point so I start sifting trough the river rock and I'm kicking up all sorts of cloudy/dirty crapl. At this point I'm worried, upset and pissed all at the same time. I have no idea what to do at this point. Yesterday I won a Biofilter off of Ebay for 61 dollars. Its called a back yard pro 1000 gal UV bio pond multi stage filter. I cant find anything on the internet about it. Does or has anyone ever heard of that model filter? The description says it only had water run through it just to make sure it worked. It comes with everything I'm guessing accept for the UV light. If in fact that it doesn't come with the light what size light should I put in it? It also has a back flush system and a indicator window. I Know now that i'm going to need a bigger pump for the new bio filter but that's going to have to be next paycheck! I'm working with what I have right now LOL! Should I slowly get rid of the river rock in the pond? If so what should I put on the pond? I will also be getting a gravel cleaner soon. should I attempt a water change or should I wait it out until I get the new bio filter? All the fish seem to be happy, I'm the one whose not happy right now. Help please!